Actor Cory Monteith has checked into a rehabilitation centre to address substance addiction issues.

The Glee star, 30, voluntarily sought professional help to face up to his demons, his representative tells People.com.

The spokesperson states, "(Monteith) has voluntarily admitted himself to a treatment facility for substance addiction. He graciously asks for your respect and privacy as he takes the necessary steps towards recovery."

Monteith, who is dating his Glee co-star Lea Michele, has been open about his drink and drug habit in the past, revealing in 2011 that he had previously checked into rehab when he was 19 years old.